anyone ever played an entire game without so much as one set of doubles rolled?

Thad: She probably would have rolled more doubles, but that was the end of the game.

Nope, probably not. 1/6 in fact. ;)

Backgammon Championships-No.70

Feel free to enter.

And her first move in the next game was with 6-6!

Someone asked about doubles on several consecutive rolls about a week ago. My opponent rolled 5-5, 6-6, 6-6, 2-2, 5-5, 6-6... right after I doubled the cube. She probably would have rolled more doubles, but that was the end of the game.

Backgammon (trambu4ka vs. Thad)

Thad: There is no general answer for that, it depends on the rolls. The general principle is that doubles being a great roll, you want to focus on offense. This is because the positions where both players anchor high are mostly about equal, while prime against prime positions are not.
But tactics often overrule that principle. 3-3 is one of the most difficult rolls. The 3 is not a great point, but making it unloads the stack on the 6. The 5 is great, but making it abandons the 8. The 10 is not great, but it unstacks the midpoint. The defensive 20 is great, but you would like to focus on attack.
After an opening 6-1, the value of advancing the back checkers goes up, so I like your move. At www.bgonline.org there are all rollouts for all second moves that are considered non-trivial, and 24/21(2) 13/10(2) indeed rates as the best move.

Thad: Yes indeed, advance the back checkers and move the 13-10 or 6-3 or 8-5.

However if you need a gammon my first suggestion might still be better. )

grenv: My opponent opened the game with 6-1 and blocked his seven-point. I moved 24/21(2) and 13/10(2). It seemed a little more important to advance my back checkers with that seven-point blocked.

Thad: double 3s should move 8-5(2) 6-3(2) probably. Possible 13-10(2) in some cases, particularly if you can hit an opponents piece.

Thad: I kind of lean towards blocking rather than a quick run, but it also depends on the opening roll of your opponent as well, but again, I like the block move over the run.

Czuch Czuckers: Ok, well, I suppose you're right. My opponent won the opening roll, then I rolled the double 3s. I suppose what I am really wondering is is it better strategy to pull your stones out of your opponent's home with a good double roll early in the game, or use the double to establish blocks of your own in/near your own home?

Thad: Sorry, that wasnt very helpful

Anyway, here are the accepted opening moves
http://www.bkgm.com/openings.html

Thad: You cannot roll doubles on the first roll of a game....

When I roll doubles on my first roll of the game is it better to advance my stones farthest from home? Or should I have constructed some blockades? How do players feel about advancing stones out of the opponent's home vs keeping one or two in there for hitting purposes, especially early in the game?

anyone for a quick backgammon?

AbigailII: I'm playing a game where there are 61 (43vs 18 with 17 already off)

I'm wondering, what's the record amount of stones in a cloning backgammon game? I'm currently playing a game that has 57 stones (33 vs 24) on the board, and there's still the possibility that more will appear.

Czuch Czuckers:  Exactly.  Also, doubles on the average contain more pipcount than non-doubles, so there are more positions that can be ended by a double.

alanback: Thats because doubles can end games with one, two, three, or four pieces remaining.

Where non doubles can only end a game with one or two pieces remaining.

Czuch Czuckers:  Statistically, it seems that a double is relatively more likely to be the last roll of a game than a roll that is not a double.  That is, for example, double 2 will end more games (or at least more than half as many) than 5-3.  This is just an impression.

Thad: It seems to me like more doubles are rolled near the ends of many of my games. I

LOL... I thought the same sometimes. I always seem to get doubles on my last turn when I dont need it

Thad:  I once did some statistical analysis on the dice rolls at ItsYourTurn because I was convinced they were skewed.  I had no luck proving this, as it turned out that the distribution of rolls was pretty close to random, with some slight bias for or against particular results.  I imagine you would find the same here.  I don't recall whether I did a systematic study of consecutive doubles.  I still have the database around somewhere.

Does Fencer keep a record of the dice rolls? If not, perhaps he could. If so, does he publish them? It would be interesting to run some statistical analysis on them to see how random they are.

If you think about how many games have been played here, the odds might actually be pretty good for someone to have thrown 1-1, 1-1, 1-1 by now like Andersp did. It probably should have (and probably has) occurred several times.

It seems to me like more doubles are rolled near the ends of many of my games. I'm assuming that it just looks like that to me, though.

Czuch Czuckers: LOL...try to do that at your kitchentable with real dice :)

Andersp: I saw 3 double ones in a row followed by 2 double 4s

No it was actually 4 double ones followed by the 2 double 4s

playBunny: I must have sacrified a lot to the dice Gods...3  random double ones in a row so far, wondering what the record is? LOL

alanback: How? Like you said, It satisfies monkey curiosity. But you said it was only monkey curiosity, which value cuts your off from understanding it's experiential benefit. I love knowing what my opponent's dice are when I play at Gold Token and DG (when the move-ahead hasn't stopped on my turn). But, then again, I am a very curious, er, bunnkey!

Another reason, though it wouldn't apply to many people, is that feedback is of most benefit when it immediately follows a behaviour. Thus, by seeing the dice immediately, you can tell if your spell or sacrifice to the Dice Gods worked or not.

alanback: I don't care to argue the point with you. How about a match instead. ;-)

Thad:  That's what I meant by monkey curiosity.  Sure, I have that too. But it isn't a compelling reason to see the dice.  Or to ask Fencer to do more programming when there other more important features that could be implemented.

alanback: I dont think there is any compelling reason to see dice before an opponent moves....

But why hide them either????

The point is that they are already rolled, supposedly, so why not display them???

Thad: Just makes it worse. The dice are rolled and they STILL won't make a frigging turn. arg

alanback: Don't you ever want to 'look ahead'? ;-)

Say you just made a nice blockade with a hole in it. Maybe your opponent can get thru it, but only with a roll of 5-3. If it's a slow-playing opponent, you might not see the result for several days. I'd like to be able to see the dice roll right away (when possible).

Thad:  How?  

It would enhance the gaming experience! ;-)

Thad:  I don't see any compelling reason for a player to be able to see his opponent's dice before the opponent moves.  It's nothing but monkey curiosity that makes us want to know what's going to happen next.  There's nothing we can do anyway, except maybe resign, and we can always do that when the turn comes back to us.

The problem is that the way Fencer wrote the original code, the dice weren't rolled until a player looked at his turn. It needs to be changed to implement many of the changes we'd all like to see, but that's a lot of programming.

Vikings: No, that is not correct. He had open options available on previous turns as well, but his dice roll didnt allow a move. Then after 3 turns like this, where i moved and stayed here, then it was not my turn again, but the dice did not show!

Family Man: because if he can move, the dice won't roll until he rolls them

skipinnz: yeah, but why?? what sense does that make? If it has already been rolled anyway, then why does it matter if i see it?

It makes me wonder, if it has been rolled, and I cant see it, then i wonder what could be happening behind the scenes? maybe nothing, but it leaves doubts!

Family Man: I think you've answered your own question, when he can't move you see what he has rolled but if he can move you are denined seeing the dice until he views the game.

How come, in an auto pass game, when I "move and stay here" and my opponent cannot make a move, the dice are displayed for their roll, and it is my turn again.

But when I do the same and I find it not my turn again, my opponents dice roll is not displayed????

This so called auto pass of fencers is really a disaster isnt it?

Cloning BG, as I defined the game, the (my) rules say that captured pieces count as Race pieces. We should try this: the new cloned pieces would count as captured pieces instead. If no one can move, the game ends as a draw.

alanback: And most importantly, the FIBS formula is perfectly compatible with the BK formula. I told Fencer long ago that I was able to give him a formula that implemented the FIBS trick for taking into account the length of the match, while leaving the BK formula unchanged for single games. He seemed to be OK with the idea of changing the formula, but not willing to implement it any time soon.

It is not a backgammon-specific problem. The current rating system could also be exploited by playing multi-games chess matches against weaker players.

Thad:  There are perfectly good backgammon ratings systems already available.  FIBS and Dailygammon use the same formula, and it works great.

alanback: I made a request for something to fix this a while back. I thought my idea was good, but I guess not enough others did.
Feature requests (Thad, 2007-07-15 06:55:25)

tippyc:A proper ratings system would make adjustments which reflect the probability of the outcome.  This in turn is a function of the relative strengths of the players and the length of the match.  The longer the match, the greater the probability that the stronger player will win.  Therefore, if the stronger player does win, the change in ratings should decrease with the length of the match.  If the weaker (i.e. lower-rated) player wins, then the change in ratings should increase with the length of the match.

Thad: i think it should be worth a bit more, as well a multi game match should be worth more, depending on how many points you win by, but i realize implementation of that could be difficult

alanback: What, the one where a match is a match is only a game even if it's a match with a million games?

Or the one where a match is a match is a CHESS match?

alanback: Ok.

Thad:  Don't even go there.  That's a closed subject here.